It’s a common scene around the Phoenix area when temperatures hover at obscenely hot levels: garage doors that are cracked open a few inches.

Some people think opening the door a smidge will help keep their garages and adjacent rooms a bit cooler.

But does this really work? And could it invite unwanted critters — or even people — into your home?

To find answers, we contacted three local experts.

Garages hold a lot of heat, especially in the Phoenix area during summer when it's hot.(Photo: iStock)

Question: Does opening your garage door a crack on a hot day keep it any cooler?

“The best way to keep your garage cooler is to make sure it is properly insulated and sealed, just like in your home, to keep cool air inside during the summer months.”

Mike Donley, president of Donley Service Center

Answer: “Yes. Venting the garage can help make it cooler because the garage holds a ton of heat,” said Mike Donley, president of Donley Service Center, 11062 N. 24th Ave., Phoenix.

“That heat can infiltrate your house through the common walls. Oftentimes, rooms adjacent to and above the garage are the hottest in the house because of this buildup of heat. Some garage doors have vents in them, but cracking the garage door relieves some of the heat.

"The best way to keep your garage cooler is to make sure it is properly insulated and sealed, just like in your home, to keep cool air inside during the summer months.”

Q: Could this practice lead to break-ins?

A: “In my personal and professional opinion, I would never recommend leaving your door open or cracked,” said Frank Vargas, owner of Security Garage Door, 6424 E. Greenway Parkway, Scottsdale.

Could leaving your garage door open lead to a break-in?(Photo: Getty Images/iStockphoto)

"Most people use their garage door as the main access to their homes and usually do not lock the door from the home to the garage.

"In addition, common items stored in garages other than cars are tools, lawn equipment, sports gear, bicycles and many other small items that would be easy pickings for unsavory types.

"If comfort of the home is a concern a much better solution is an insulated door. Insulated garage doors can have up to an R18 rating, where an uninsulated door is R-0, therefore helping keep the garage and home cooler.”

Q: Are spiders, snakes or other critters likely to invade my house through a cracked-open garage door?

A: “Leaving the garage door open is going to invite a whole host of potential issues,” said Ernie Henson, president of Stormin’ Norman Termite and Pest Control, which serves the southeast Valley and Maricopa. “Most creepy-crawlies enter our homes through doors and windows that are left open or do not seal correctly.

Black widow spiders often are found in garages and closets.(Photo: Blue Sky Pest Control)

"Under shelving is the perfect place for a black widow or rodent to set up shop. Those cardboard boxes you have been meaning to get rid of are the perfect place for crickets or scorpions to harbor. The pet food stored on the shelf can invite ants or mice if not in a sealed container. The water softener may have enough condensation to support the water needs for every pest that enters your garage.

"So what can be done to help prevent an invasion? First, I would recommend regular pest service. Having a barrier around the home helps insects from being able to take up residence. Insulation of a garage door is also a great solution to keeping pests away and keeping your energy bill down.”